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Baekma, a new standard chrysanthemum (Dendranthema grandiflorum [D. morifolium]) cultivar, was released by National Horticultural Research Institute (NHRI), Rural Development Administration, Korea Republic, in 2004. The cross was ...
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Baekma, a new standard chrysanthemum (Dendranthema grandiflorum [D. morifolium]) cultivar, was released by National Horticultural Research Institute (NHRI), Rural Development Administration, Korea Republic, in 2004. The cross was made in 2001 between Baeksun, a summer flowering cultivar, and Shinma, an autumn flowering cultivar. The characteristics are investigated from 2002 to 2004 for the evaluation and selection of this cultivar, including shading culture in summer and retarding culture in autumn. The natural flowering time of Baekma is late September, but year-round flowering is possible by shading and lighting. It has large flower, ~13.8 cm in diameter, the number of the petals is 254 and the shape of the outer petals is tubular. The flower is white, but shows light green in its centre at the early stage of flowering. The days to flower from short day treatment is ~51 in autumn..
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Four true breeding genetically diverse genotypes of flax with contrasting seed colour viz., Aoyagi (brown), TL-33 (yellow), Solin (yellow) and Janaki (brown) were crossed among each other as Aoyagi x TL-33 and Solin x Janaki to de...
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Four true breeding genetically diverse genotypes of flax with contrasting seed colour viz., Aoyagi (brown), TL-33 (yellow), Solin (yellow) and Janaki (brown) were crossed among each other as Aoyagi x TL-33 and Solin x Janaki to develop F1, F2 and back cross generations for studying inheritance of seed colour in two environments i.e. CSKHPKV Palampur and RWRC, Malan during 2006-07. F1's of Aoyagi x TL-33 and Solin x Janaki had brown colour of seeds. This indicated the dominant nature of brown seed coat colour over yellow. The F2 segregation gave a good fit to the expected ration of 3 brown: 1 yellow in both the crosses. Similarly for flower colour, four true breeding genetically diverse genotypes of flax viz., Him Alsi2 (white), Chambal (blue), Him Alsi1 (white) and Canadian line (blue) were crossed among each other as Him Alsi2 x Chambal and HimAlsi1 x Canadian line to develop F1, F2 and back crosses. The F1's of cross combinations Him Alsi2 x Chambal and HimAlsi1 x Canadian line had blue flowers which indicated that blue flower colour is a dominant trait. The dominant nature of blue flower colour over white flower colour was further confirmed by back crosses and F2's wherein two distinct classes were observed in both the environments.
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'Royalty' crabapple (RC) (Malus hybrid) is one of the most favored introduced crabapples in China. Chinese flowering crabapple (CFC), Malus spectabilis (Aiton) Borkh, has been used for ornamental trees in China for a long time. Wi...
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'Royalty' crabapple (RC) (Malus hybrid) is one of the most favored introduced crabapples in China. Chinese flowering crabapple (CFC), Malus spectabilis (Aiton) Borkh, has been used for ornamental trees in China for a long time. With the beginning of breeding research on crabapple in China, it is important to compare the ornamental characters between CFC and RC. The 3-year-old grafted trees on 6-year- old Malus robusta (Carr.) Rehd (Pyrus prunifolia var. robusta Carr) rootstocks were used to compare their ornamental characters between CFC and RC. The results of 2004-2006 investigation in Beijing showed that CFC had a higher flower density per length of shoot, larger flower size and more petal number in each flower than RC. The petal color of CFC changed from red to pink or white with the opening of flower, though showing a lighter color, but its leaves kept green, unlike RC which has dark red leaves throughout its life. CFC had more fruit number per shoot length, larger fruit size, and later fruit abscission, but with green fruit color unlike 'Royalty', whose fruits showed a dark red color. CFC had a stronger tree vigor, with more shoot growth in length and diameter than RC.
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Droneflies, imagoes of the hoverfly Eristalis tenax, are known to possess a preference for yellow flowers, i.e. they prefer to visit yellow flowers and prefer to extend the proboscis to yellow colours. In this study we disentangle...
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Droneflies, imagoes of the hoverfly Eristalis tenax, are known to possess a preference for yellow flowers, i.e. they prefer to visit yellow flowers and prefer to extend the proboscis to yellow colours. In this study we disentangle these colour preferences by investigating the landing reaction and proboscis reflex with particular reference to intensity, spectral purity and dominant wavelength of colour stimuli and their UV reflection properties. In multiple-choice tests, naive and non-trained flies prefer to land on yellow colours independent of their UV reflection characteristics, but also accept blue, white and pink colours if they absorb UV and are of sufficient brightness. Flies trained to land on colours other than yellow still prefer yellow colours to some extent. Moreover, the flies prefer bright over dark yellow colours even if trained to dark yellow ones. The flies refuse to land on dark colours of all hues. Naive flies exhibit the proboscis reflex only to pure yellow pollen. These experiments show for the first time that landing in droneflies is triggered by a yellow colour independent of its UV reflection properties, but proboscis extension is triggered by yellow colours strongly absorbing blue and UV. The ability to discriminate colours is better than predicted by the categorical colour vision model. The colour preferences in E. tenax represent a fine-tuned ability to visit yellow flowers displaying a UV bull's-eye pattern.
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The research was carried out over two years in the coastal zone of Salerno. In the first year, plantlets were transplanted on 15 December and 12 white and 15 coloured hybrids were tested and compared with the commercial cultivars ...
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The research was carried out over two years in the coastal zone of Salerno. In the first year, plantlets were transplanted on 15 December and 12 white and 15 coloured hybrids were tested and compared with the commercial cultivars Snow Wonder and Maria (white) and Fressia (red). In the second year, the crop was transplanted on 30 October and 11 white and 12 coloured stocks were compared with the cultivars Maria and Julliette (yellow). Plants were grown on mud-clay soil at a density of 22 plants m-2. In the first year, flowering occurred in March, starting from 11 to 14 weeks after transplanting, and the harvests lasted 18 days on average for white and coloured hybrids. In the second year, flowering started in the middle of February, from 13 to 17 weeks after transplanting, and the length of the harvest period was 4 and 5 weeks in the first and in the second group, respectively. Seven white hybrids (S1072, S1074, S1070, S1073, S1088, S1089, S1090) reached the minimum levels of 14 and 20 flowers stems per m2, obtained in the commercial cultivars in the first and the second growing cycle, respectively. Among the coloured stocks, 3 hybrids tested in both years produced more than 13 stems per m2 (S1095 fuchsia, S1091 pink, S1094 lilac). The same level was reached also in 5 hybrids used in only one year (S1092 lilac, S1082 yellow and S1097, S1098, S1099 red). All the most productive hybrids gave flower stems of the First Quality Class (stem length >60 cm and raceme length >15 cm).
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Five parents of common vetch (Vicia sativa L.) having orange/beige cotyledon colour, brown/white testa colour, purple/green seedling colour and purple/white flower colour were crossed as a full diallele set. The inheritance patter...
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Five parents of common vetch (Vicia sativa L.) having orange/beige cotyledon colour, brown/white testa colour, purple/green seedling colour and purple/white flower colour were crossed as a full diallele set. The inheritance patterns of cotyledon, testa or seed coat colour, flower and seedling colour, were studied by analyzing their F1, F2, BC1 and BC2 generations. The segregation pattern in F2, BC1 and BC2, showed that cotyledon colour was governed by a single gene with incomplete dominance and it is proposed that cotyledon colour is controlled by two allelic genes, which have been designated Ct1 and Ct2. Testa colour was governed by a single gene with the brown allele dominant and the recessive allele white. This gene has been given the symbol H. Two complementary genes governed both flower and seedling colours. These flower and seedling colour genes are pleiotropic and the two genes have been given the symbols S and F.
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Red flowers are a defining character of the bird-pollination syndrome. Birds do not, however, innately prefer red, suggesting that rather than attracting birds, red flowers may serve to exclude other visitors (e.g., bumblebees). B...
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Red flowers are a defining character of the bird-pollination syndrome. Birds do not, however, innately prefer red, suggesting that rather than attracting birds, red flowers may serve to exclude other visitors (e.g., bumblebees). Bees are sometimes considered "blind" to red, but studies have in fact documented both blue and red preferences in various bee species. These mixed results may be an effect of overly simplistic lab settings. We hypothesized that bees might readily locate red flowers in a simple laboratory environment, but struggle to find the same flowers in a complex, foliated setting. We tested the effects of environmental complexity on visitation to red and blue artificial flowers and on the foraging rate of captive worker bumblebees (Bombus impatiens). Bees made significantly fewer visits to red flowers when foraging in a complex environment with artificial green foliage, suggesting that red becomes harder to locate in this context than in a simple, leafless environment. Bees also foraged more slowly, on average, in the complex environment, although the difference was apparent only among experienced bees. Our findings provide a possible explanation for previous laboratory tests finding no colour preference in bumblebees. This "contextual colour-blindness" of bees supports the hypothesis that red evolved as a mechanism for plants to avoid visitation by bees, favouring bird pollination instead.
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Colour constancy is the perceptual phenomenon that the colour of an object appears largely unchanged, even if the spectral composition of the illuminating light changes. Colour constancy has been found in all insect species so far...
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Colour constancy is the perceptual phenomenon that the colour of an object appears largely unchanged, even if the spectral composition of the illuminating light changes. Colour constancy has been found in all insect species so far tested. Especially the pollinating insects offer a remarkable opportunity to study the ecological significance of colour constancy since they spend much of their adult lives identifying and choosing between colour targets (flowers) under continuously changing ambient lighting conditions. In bees, whose colour vision is best studied among the insects, the compensation provided by colour constancy is only partial and its efficiency depends on the area of colour space. There is no evidence for complete 'discounting' of the illuminant in bees, and the spectral composition of the light can itself be used as adaptive information. In patchy illumination, bees adjust their spatial foraging to minimise transitions between variously illuminated zones. Modelling allows the quantification of the adaptive benefits of various colour constancy mechanisms in the economy of nature. We also discuss the neural mechanisms and cognitive operations that might underpin colour constancy in insects.
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In this paper, we described the mineral contents of 11 different accessions of balloon flower {Platycodon grandiflorum) collected from China and Korea. The roots of balloon flower plants with blue flowers had greater concentration...
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In this paper, we described the mineral contents of 11 different accessions of balloon flower {Platycodon grandiflorum) collected from China and Korea. The roots of balloon flower plants with blue flowers had greater concentrations of five important minerals-Ca, Fe, Mg, Mn and Zn than did the roots of plants with white flowers. In most cases, the concentration of minerals in the roots of plants with blue flowers was nearly twice that of plants with white flowers. Concentrations of Ca and Mg were much higher than concentrations of the other minerals assayed in the roots of all plants, regardless of flower colour. Accession CB02 had blue flowers and its roots contained the highest levels of Ca, Mn and Zn. Accessions CB01 and CB05, which also had blue flowers, had roots with the highest amounts of Mg and Fe, respectively. Among the accessions, CB02, might suitable to use commercially as its mineral content was much higher than that of any other tested accession.
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